Fermented herring


Surströmming (fermented Baltic herring or, literally, soured Baltic herring), is one of Sweden's most infamous products and is especially popular in northern Sweden.

Surströmming can only be made from strömming (Baltic herring), which are smaller than sill (Atlantic herring). The strömming used for surströmming are caught just prior to spawning and the fermentation starts from a lactic acid enzyme in the spine of the fish which releases pungent smelling acids as well as hydrogen sulphide! Despite this many Swedes still love surströmming!

Fermented fish is not really so strange. The ancient Greeks and Romans made a famous sauce from fermented fish and Worcestershire Sauce also has a fermented fish ingredient.

It is usually opened outside!

When opened, surströmming releases a strong and sometimes overwhelming odour so it is usually eaten outside. Surströmming are normally eaten at the end of August but I've met Swedes who like to bury a can outside in snow and eat some at Christmas!

I also remember a case where a Swede in Gothenburg opened a tin in his apartment block, which caused the whole apartment block to be evacuated because someone smelt the fish and thought there was a gas leak! Indeed, according to a Japanese study, a newly opened can of surströmming has one of the most putrid food smells in the world! I don't know how they measured this, but I can easily believe the result.

Who likes it?

We carried out a poll to find out how many people like surströmming.  Out of 478 people who took part in the poll, only 31% said that they liked it, whilst 69% said that they hated it! (32% of people who took part in the survey said that the smell was so bad that they refused to taste it!)

But Mimmi likes it!

I have spoken to literally hundreds of young Swedes about surströmming and most either hate it or tolerate it because they enjoy the party atmosphere when a can of surströmming is opened. But then I met Mimmi...

Mimmi is from the north of Sweden and is spending a year working at TotallySwedish in London. She is genuinely enthusiastic about surströmming. She explained, "I kind of grew up eating it. My parents love it and although I didn't like it when I was younger now I really love it. I eat it every now and then: it's not a big deal back home. I eat it all-year round, but mainly outside in the summer, especially in August."

"When I had some English friends staying
they couldn't stay in the house once I had opened a can
of surströmming!"

Most people I have met who like surströmming are only ever allowed to eat it outside, but Mimmi's family eat it inside as well. "We get use to it so we often eat it inside the house, although when I had some English friends staying they couldn't stay in the house once I had opened a can of surströmming!"

"I really like the smell now. It reminds me of good food and as I like fish and strong flavours I just adore surströmming. I eat it on crispbread with potatoes, sour cream and dill."

Poor Mimmi hasn't had any surströmming since she has been in London. She explained that, "I am not allowed to open it in my house and although I have tried to get some friends to go with me to a park and eat some, so far I haven't convinced anyone!"

A glass of snaps has been the incentive for most people I have met who have eaten surströmming, but Mimmi is quite happy enjoying her fermented herring with nothing more than a glass of water!

A surströmmingsskiva!

For most Swedes who eat surströmming the reason is simple: it is because they like a surströmmingsskiva (a fermented herring party). Swedes love an excuse for a party and opening a can of rotting fish can provide an excuse. Really.

"Yes, ok it smells awful and doesn't taste very nice", the argument goes, "but we always have a good party when we open a can of surströmming!"

So if there is lots of snaps on offer it can be worth eating surströmming, according to some. I can think of better reasons for a party... 

How is it made?

The herring are caught in May, when they are in prime condition and just about to spawn. They are then put into a strong brine for about 20 hours which draws out the blood. The heads are then removed and they are gutted and put into a weaker brine solution. Canning starts at the beginning of July and goes on for about five weeks. The first cans go on sale on the third Thursday in August.

Storing the cans

The cans must be stored in a fridge as fermentation continues in the can which causes the can to bulge noticeably. (The can on the left above is over 12 months old and is bulging noticeably more than the 1 month old can on the right.)

Apparently, it is a myth that cans will explode if not opened. There have been no know cases of surströmming cans exploding although they are not allowed on planes leaving the UK, but they are allowed on planes leaving from Sweden!

Eating surströmming


Surströmming is usually eaten in a sandwich (called surströmmingsklämma) made with tunnbröd (thin bread), which is normally buttered. The tunnbröd is then topped with:

•  sliced mandelpotatis (a type of potato grown in northern Sweden which is slightly sweet and waxy),
•  fillets of surströmming (sometimes they are cut up into small pieces),
•  finely diced red onion.

In southern Sweden, some crème fraîche or gräddfil (which is a bit like soured cream) is added along with chives, tomato and chopped dill.


Surströmming sandwiches are usually served with some Västerbottensost (a type of hard cheese), snaps and lager, although some people claim that milk is the best thing to drink with surströmming sandwiches.

If you get invited to surströmmingsskiva why not try it? You might like it!

John Duxbury



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